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51.
目的:研究案例教学法结合多媒体教学法在超声专业教学中的应用效果。方法:选择2015年3月到2017年3月在我院超声科实习的112名医学院学生进行研究,按照随机数字表法将医学生分成观察组及对照组,各56例,对照组采用传统教学法实施教学,观察组则采用案例教学法以及多媒体教学法实施综合教学,在每学期末,统计并对比两组学生理论成绩和实践成绩,以及两组学生对教学方式的满意度。结果:观察组的理论成绩和实践成绩各项目分值均分别明显高于对照组,差异均有统计学意义(均P0.05)。观察组学生对教学方式的满意度为98.21%,明显高于对照组的87.50%,差异有统计学意义(P0.05)。结论:案例教学法与多媒体教学法的综合应用能够有效提升超声专业学生的理论成绩和实践成绩,还可改善其对教学方式的满意度,效果较好,临床超声教学可考虑将此种教学方式进行广泛推广,从而更有利于培养专业人才。 相似文献
52.
由于微生物知识在理论和实践中具有重要的作用,加强微生物教学,帮助学生获得系统的微生物学知识体系是相关专业教师的工作目标。在教学中激发学生兴趣是教师达到教学目的一个重要环节,主要阐述了让学生参与课堂教学、利用多媒体教学、优化教学内容和理论联系实际等4方面的内容。 相似文献
53.
研究性实验教学模式的探讨 总被引:4,自引:1,他引:4
从教学过程、教学效果等方面探讨了微生物学实验课程实施研究性实验教学模式的必要性以及具体实施的方法。实践表明,研究性实验教学模式对培养学生的创新意识,提高学生的实践能力等方面有积极的作用。 相似文献
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On the fate of orally ingested foreign DNA in mice: chromosomal association and placental transmission to the fetus 总被引:12,自引:0,他引:12
We have previously shown that, when administered orally to mice, bacteriophage M13 DNA, as a paradigm foreign DNA without
homology to the mouse genome, can persist in fragmented form in the gastrointestinal tract, penetrate the intestinal wall,
and reach the nuclei of leukocytes, spleen and liver cells. Similar results were obtained when a plasmid containing the gene
for the green fluorescent protein (pEGFP-C1) was fed to mice. In spleen, the foreign DNA was detected in covalent linkage
to DNA with a high degree of homology to mouse genes, perhaps pseudogenes, or to authentic E. coli DNA. We have now extended these studies to the offspring of mice that were fed regularly during pregnancy with a daily dose
of 50 g of M13 or pEGFP-C1 DNA. Using the polymerase chain reaction (PCR) or the fluorescent in situ hybridization (FISH)
method, foreign DNA, orally ingested by pregnant mice, can be discovered in various organs of fetuses and of newborn animals.
The M13 DNA fragments have a length of about 830 bp. In various organs of the mouse fetus, clusters of cells contain foreign
DNA as revealed by FISH. The foreign DNA is invariably located in the nuclei. We have never found all cells of the fetus to
be transgenic for the foreign DNA. This distribution pattern argues for a transplacental pathway rather than for germline
transmission which might be expected only after long-time feeding regimens. In rare cells of three different fetuses, whose
mothers have been fed with M13 DNA during gestation, the foreign DNA was detected by FISH in association with both chromatids.
Is maternally ingested foreign DNA a potential mutagen for the developing fetus?
Received: 15 April 1998 / Accepted: 15 June 1998 相似文献
57.
有不少利用PEG法把外源基因导入到大豆原生质体,获得了转基因植株的报道,目前PEG的转化效率有所提高,但还是不能满足转化的需要,如何提高原生质体的转化效率是基因转化工作中的关键问题。本实验为了解决这个难题,以大豆幼子叶原生质体为材料,利用聚鸟氨酸(PLO:Poly-L-Ornithine,MW:114900,SIGMA)对Bt基因的转化进行了探讨。 相似文献
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应用硫氧还蛋白促进外源蛋白在大肠杆菌的可溶性表达 总被引:4,自引:0,他引:4
为了观察硫氧还蛋白(TrxA)促进外源蛋白在大肠杆菌中可溶性表达的作用,我们从质粒pET-32a(+)上克隆了trxA基因,构建了TrxA表达质粒pT-TrxA。将该质粒与其它蛋白基因的表达质粒共同转化E.coli并同时获得表达。结果表明,共表达TrxA可以明显促进外源蛋白,如甲状旁腺激素相关蛋白(PTHrP)、PTHrP受体(PTHrP-R)的血管内皮生长因子(VEGF)的可溶性表达。说明共表达 相似文献
60.
Achraf Ammar Omar Boukhris Hsen Hsouna Imen Ben Dhia Khaled Trabelsi Tariq Ali Gujar Cain C.T Clark Hamdi Chtourou Tarak Driss Anita Hoekelmann 《Biology of sport / Institute of Sport》2021,38(4):683
Although napping is commonly used as a strategy to improve numerous physical and cognitive performances, the efficacy of this strategy for improving postural balance has not yet been elucidated. Thus, the aim of this study was to conduct a comprehensive examination of the effect of a 60 min nap opportunity (N60) on different components of postural control. Ten highly active individuals (age = 27 ± 3.5 y, height = 1.75 ± 0.52 m, weight = 66.02 ± 8.63 kg) performed, in a randomized order, two afternoon test sessions following no nap (NN) and N60. Postural balance was assessed using the sensory organisation test (SOT), the unilateral stance test (UST), and the limits of Stability Test performed on NeuroCom® Smart Balance Master. The subjective rating of sleepiness before and after the nap conditions was also assessed. Compared to NN, N60 improved the composite balance score (p < 0.05, ES = 0.75, Δ = 5.3%) and the average and maximum percentage balance in the most challenging postural conditions of the SOT (p < 0.05 for SOT-4 and 5 and p < 0.0005 for SOT-6; ES range between 0.58 and 1.1). This enhanced postural balance in N60 was accompanied with improved visual (p < 0.05; ES = 0.93; Δ = 8.9%) and vestibular (p < 0.05; ES = 0.81; Δ = 10.5%) ratios and a reduced level of sleepiness perception (p < 0.001, ES = 0.87). However, no significant differences were found in any of the UST and LOS components’ scores (p > 0.05). Overall, a 60 min post lunch nap opportunity may be viable for improving static balance, although further work, involving larger samples and more complex motor activities, is warranted. 相似文献